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In order to ensure the health and safety of occupants, buildings must be inspected to check their compliance to current regulatory requirements prompted by occupancy changes, renovations and building code revisions. Recent inspections conducted by Public Works Canada have identified about 1700 occurrences of code violations in 19 buildings. There is an enormous amount of information that can be extracted from the study mentioned above to implement a knowledge‐based expert system to assist in future building inspections. The philosophy of this expert system is to integrate both knowledge‐based and hypertext representation techniques to enable building inspectors to quickly identify code violations, refer to the code text and provide case study information that can assist in resolving a problem. The present paper describes the development framework and details of a prototype implementation known as the Health and Safety Expert System (HASES). The HASES currently addresses the requirements of ‘Section 3.4: Requirements for Exits’ of the 1990 National Building Code of Canada. The software architecture consists of an external database of building details, an object hierarchy and a rule‐base representing the code requirements, hypertext user‐interface for code text and case study information. The ultimate objective is to make this system available for field inspections using notepad computers.

An important part of the knowledge required for designing the envelope of a new building is based on experience. Confronted with a building envelope design problem, a human expert adds to well‐established domain knowledge his/her own experience or the experience of others, to support his/her reasoning process, and to guide him/her in stereotypical situations. Based on that observation, we can conclude that the building envelope design fits well the description associated with the so‐called “weak theory domains”, and is a prime candidate for adopting a case‐based reasoning (CBR) approach. Proposes strategies to encode, organize, and compare prototypical building envelope cases within a CBR framework for selecting the construction alternatives during the preliminary stage of the building envelope design. The methodology presented aims to find the most suitable design alternative for a new building envelope from a library of prototypical building cases.

Organic coatings remain the most widely used way of protecting steel structures from corrosion. Traditional anticorrosive paints contain lead or hexavalent chromium compounds as active pigments. The use of these classical chromates is nowadays restricted by increasing environmental awareness and stringent national and international regulations. An alternative is the use of ion‐exchangeable pigments. The purpose of this paper is to show that cation‐exchanged zeolites can be considered as a safe and efficient alternative to traditional hazardous pigments in protecting steel surfaces.

The new pigments were characterised using different analytical and spectro‐photometric techniques. Characterisation of these pigments using X‐ray diffraction and scanning electron microscopy were done. X‐ray fluorescence was employed to elucidate the concentration of different elements in the prepared pigments. Evaluation of the ion‐exchanged and initial zeolite pigments using international standard testing methods (ASTM) was estimated. Testing the anticorrosive protection of cation‐exchanged zeolites in alkyd paints formulated based on their pigment volume concentration/critical pigment volume concentration was studied, and then these new pigments were applied on cold‐rolled steel panels. The physico‐mechanical properties of dry films and their corrosion properties using accelerated laboratory test in 3.5 per cent NaCl for 28 days were tested.

The results of this work revealed that paint films containing initial Na‐zeolite performed the least protection behaviour, while films including Zn, Ca and Mg‐zeolites were better in their corrosion protection performance, and they can be arranged as Zn‐zeolite>Ca‐zeolite>Mg‐zeolite.

These pigments can be applied in other polymer composites, e.g. rubber and plastics as reinforcing agent and fillers.

The paper shows that these prepared pigments are environmentally friendly pigments which impart high anticorrosive behaviour to paint films with great economic savings.

Ion‐exchange clays containing sodium such as bentonite and montmorillonite have the ability to exchange their cations. Few studies conducted with this type of ion‐exchange pigments are not conclusive about their anticorrosive efficiency. The present research aims to address the study on the anticorrosive efficiency of this type of pigments in chlorinated rubber paints. Sodium‐bentonite was exchanged with Zn, Sr and Zn‐Sr to be applied on low carbon steel specimens and study the anticorrosive performances of these new ion‐exchanged bentonites (IEBs) in anticorrosive paint formulations.

The new pigments were characterised using scanning electron microscopy (SEM) and X‐ray fluorescence (XRF) to determine the CEC (cation exchange capacity) of the different exchanged cations. Evaluation of the ion‐exchanged and Na‐bentonite pigments using international standard testing methods (ASTM) was estimated. Paint systems manufactured with these ion‐exchange pigments have been subjected to adhesion, accelerated corrosion laboratory tests, and EIS in order to assess their anticorrosive behaviour.

The results of this work revealed that the ion‐exchange bentonite (IEBs) pigments showed high anticorrosive performance that can be arranged as follows: Sr‐bentonite was better than Zn‐Bentonite and both were better than the double Zn‐Sr‐bentonite indicating an antagonism behaviour between the two cations when present together.

These pigments can be applied in other polymer composites, e.g. rubber and plastics as reinforcing agent and fillers.

These prepared pigments are environmentally friendly pigments which impart high anticorrosive behaviour to paint films with great economic savings.

This work aims to study the corrosion protection of laboratory‐prepared micaceous zinc ferrite (MZF) pigment in anticorrosive paints for steel.

Acrylic‐modified alkyd coatings, based on MZF pigment, micaceous iron oxide (MIO) and zinc ferrite (ZF) pigments, were prepared at different pigment volume concentrations “PVCs” to the critical pigment volume concentrations “CPVCs” ratio, which denoted hereafter by A. Scanning electron microscope, weight loss measurements, water vapour transmission (WVT) and immersion in 3.5 per cent salt solution as well as physico‐mechanical properties were performed to evaluate the paints anticorrosive performance.

WVT and corrosion protection can be affected by the PVC/CPVC ratio for all systems. At any particular PVC, the barrier property of the pigment was the main factor affecting the WVT and corrosion protection. MZF pigment protected the carbon steel physically through barrier action and chemically by the reaction with the acidic acrylic‐modified alkyd resin to produce soaps which passivate the substrate.

Novel MZF paint could be used with optimum percentage in anticorrosive paints for steel protection especially in humid and coastal regions.